by bilsef, published
This parametric scad file can be customized to create bushing holders for SDP-SI press fit self aligning bushings. It can also create holders for delrin dowels to make 180 degree bushings. For my Y-Axis, I use two self aligning bushings on one shaft and two 180 degree bushings on the other shaft. Delrin (acetal) dowel pins are available from McMaster-Carr http://www.mcmaster.com/#plastic-dowel-pins or you can cut them from delrin rod. They will wear much better than PLA or ABS.
For the 180 degree bearings, you might have to print them a couple of times, making adjustments for your printer. You want them to be matched exactly to your shaft diameter.
The attached stl files are for 16mm self aligning bushings from SDP-SI and 1/8" x 1/2" long dowel pins from McMaster. They are set up for 8mm smooth rods. The bottom of the Y plate is 16mm from the center of the shafts. All of this can be adjusted in the OpenSCAD file.